Tooth point



Aug 5, H1941 c. c. HosMER Erm. 2,251,487

TOOTH POINT Filed April 17, 1939 Patented Aug. 5, 1941 TOOTH POINT Chester C. Hosmer, Long Beach, and Ernie L. Launder, Montebello, Calif.

Application April 17, 1939, Serial No. 268,254

1 Claim.

This invention relates to excavating apparatus and relates more particularly to the teeth or points of scariers, power operated shovels, ditchers, etc. A general object of this invention is to provide a dependable, long wearing, and particularly effective detachable point or cap for the tooth of an excavating implement or machine.

Another object of this invention is to provide improvements in the class of excavating tooth points described and claimed in United States Letters Patent No. 2,124,230, granted to C. C. Hosmer and E. L. Launder July 19, 1938.

A tooth point of the character disclosed in the said Letters Patent comprises, generally, a platelike body of hard wear resisting material adapted to overlie the tooth and project therefrom to form a digging spike and a housing or box on the body for embracing thetooth and formed of a malleable material adapted to be distorted or indented into recesses in the side of the tooth to -detachably secure the point to the tooth. This con-k tooth point of the character mentioned in which severe strains and heavy forces do not cause bending or distortion of the housing or box.

Another objectof this invention is to provide a tooth point of the character mentioned in which the tooth embracing box is fabricated to have a major portion of rigid strong material that does not bend, give or distort under the most severe working conditions and a malleable portion whose sides are adapted to Vbe indented into the recessed sides lof the tooth to secure the point to the tooth.

A further object of this invention is to provide a detachable cap or point for the tooth of an excavating device that is simple and inexpensive to manufacture and that is easy to apply and remove.

The various objects and features of our invention will be fully understood from the following detailed description ofl a typical preferred form and application of the invention, throughout 2.

which description reference is made to the accompanying drawing, in which:

Fig. 1 is a fragmentary plan view of the tooth of an excavating device with the improved cap or point of the present invention secured thereto. Fig. 2 is a vertical detailed sectional View of the assembly illustrated in Fig. 1. Fig. 3 is an enlarged transverse detailed sectional view taken as indicated by line 3 3 on Fig. 2. Fig. 4 is an enlarged bottom view ,of the improved cap or point removed from the tooth, being a view taken in a plane parallel with the body of the point. Fig. 5 is a vertical detailed sectional view of the housing or box of the point prior to its assembly showing the two sections ofY the boxk in spaced relation. Fig. 6 is'aview similar to Fig. 5 showing the sections or portions secured together and Fig. 'l is a view similar to Fig. 6 showing the housing or'box secured to the body.

In the drawingwe have illustrated a portion of a tooth of the character embodied in excavating devices and-apparatuafor example, on the dippers of power shovels, trenching machines, etc. The portion of the tooth illustrated includes a shank or base IIE. The base I0 is substantially rectangular in transverse cross section having flat parallel sides and iiat upper and lower surfaces II and I2. The upper and lower surfaces I I and I2 of the tooth'base II) converge outwardly or forwardly. A reduced part I3 projects forwardly from the forward face I4 of the vtooth base IB. The tooth part I3 has at, generally Aparallel sides I5 and iiat upper and lower surfaces I6 and I'I that converge outwardly or forwardly. The upper surface IB of the part I3 lies in a plane substantially parallel with the upper surface II of the base I@ while the lower surface Il of the part I3 slopes upwardly and forwardly at an increased angle relative to the lower surface I2 of thebase ID. Indentations or recesses I8 are provided in the opposite sides I5 ofthe tooth parts I3. The recesses I8 are in the rear portion of the partY I3 being spaced a short distance forwardly from the forward end face I4 of the base I0. The side walls of the recesses IS are preferably bevelled or tapered as best illustrated in Fig. 3 of the drawing.

A socket or opening I9v extends rearwardly in the tooth base IQ from its forward face I4. The opening I9 is spaced midway between the sides of the tooth base II] and its lower wall is ush with the upper surface of the tooth part I3. The opening I9 is preferably rectangular. An inclined opening 20 extends downwardly and forwardly in the tooth base IIJ from its upper surface II to the inner end of the opening I3. The forward upper corners of the tooth base Ill are bevelled or rounded off at 2l The improved tooth cap or point of the present invention may be said to comprise, generally, a body 22 forming a spike on the tooth and a housing or box 23 on the body 22 embracing the tooth part I3 and comprising a strong rigid portion A and a malleable portion B.

The body 22 is the active earth engaging member of the tooth point. As illustrated in the drawing the body 22 is a plate-like member having flat parallel upper and lower surfaces. The body 22 may be rectangular in plan elevation having straight parallel rear and front ends 2Q and 25 and having straight parallel longitudinal edges. In the preferred construction the body 22 is elongate being considerably longer than the tooth part I3. The lower side of the body 22 is bevelled oif to be in converging relation to the upper surface of the body adjacent the forward end of the body whereby the forward active edge 25 is sharpened. The tapering or bevelling of the under surface of the body 22, as just described, provides the body with what may be termed a spike or a spike portion for actively engaging the work cr earth.

The body 22 is adapted to bear flatly against the upper surfac-e I6 of the tooth part I3 when the cap or point is in position on the tooth. The body 22 is proportioned to extend laterally beyond the opposite sides I5 of the tooth part I3 and to project a considerable distance forwardly from the tooth part when the p-oint is in the active position on the tooth. Thus, as illustrated in Fig. 2 of the drawing, the tapered spike portion of the body 22 extends a substantial distance forwardly beyond the tooth part I3. The inner or rear end 24 of the body 22 is adapted to oppose or lie substantially parallel with the forward face I4 of the tooth base III. In accordance with the invention the body 22 is formed of a hard wear-resisting material to effectively resist the abrasion and wear to which it may be subjected when the tooth is in operation. The body 22 may be formed of any suitable material having the necessary or desirable characteristics. In practice the body 22 may be formed of a steel adapted to be heat treated to a high degree of hardness and to have the necessary degree of toughness to withstand the shock and abrasion during operation. It has been found practical to construct the body 22 of a high carbon steel alloy.

In the preferred construction the body 22 has engagement or cooperation with the tooth base Il! to assist in holding the cap or point on the tooth. A tongue or tang 23 projects from the inner or rear end 24 of the body 22 and enters or cooperates with the opening I9. The tag 23 is preferably an integral part of the body 22. The tang 26 is rectangular and is proportioned to fit in the opening I3. The lower side of the tang 25 forms an unbroken continuation of the lower surface of the body 22 to bear against the lower wall of the opening I9. The tang 26 preferably closely fits the opening I 9 to have its several surfaces cooperate with the walls of the opening. It will be apparent how the tang 23 fitting the opening IS assists in the transmission of the active or operating forces between the point body 22 and the tooth base Ii). The rear end 24 of the body 22 may have bevelled or rounded parts 21 opposing the rounded corners 2I of the base I0.

The housing or box 23 is provided to engage or embrace the tooth part I3 to hold or secure the tooth point in place. The box 23 is applied to or secured to the under side of the body 22 and is shaped and proportioned to closely engage about the tooth part I3. In the application of the invention illustrated in the drawing the housing 23 is substantially U-shaped in transverse cross section having spaced side walls 28 and a bottom wall 29 extending between and connecting the side walls 28. The side walls 28 of the box 23 are :dat and substantially parallel to lie closely against the sides I5 of the tooth part I3. The bottom 23 is fiat and is disposed to lie flat against the lower surface I'I of the tooth part I3. The side walls 23 of the box 23 are substantially triangular in side elevation and their upper edges 33 slope downwardly and forwardly to engage against the lower surface of the body 22. The box 23 is proportioned to receive substantially the entire tooth part I3 and when the cap or point is in position on the tooth the inner or rear end of the box 23 is in spaced adjacent relation to the forward face I4 of the tooth base It is a feature of the invention that the box 23 embodies the portion A of hard substantially unyielding material and the portion B of deformable or malleable material. The portion A constitutes the forward end part of the box 23 while the portion B is the rear part of the box. The portions A and B are separately or independently formed and are assembled and connected to constitute the box 23. The housing or box portion A is formed of steel or other material having the desired characteristics, namely, strength and rigidity. The portion B is formed of a malleable material such as soft, mild steel. The box portions A and B are arranged in end to end relation and are secured together along a line X, as shown in Figs. 5 and 6. It is preferred to integrally join the box portions A and B by welding 32. The welding 32 is preferably continuous along the line X extending across both sides of the box and across the bottom of the box.

The line X of connection between the box portions A and B is preferably spaced forwardly from the recesses I3, considering the point to be in the operative position on the tooth base. l/Vith this relationship of parts the malleable box portion B overlies or encloses the recesses I8.

The body 22 and the housing or box 23 are integrally joined to form a single unit. In the preferred construction a continuous line of welding 33 extends along the upper edges 3B of the box side walls 28 and extends across the forward edge of the bottom wall 29 to rigidly and securely join the box 23 with the body 22. In the manufacture of the tooth point the body 22 is separately formed and the box 23 may be assembled as described above, and then joined with the body 22 by the welding 33 to form a rigid integral unit. The body 22 may then be heat treated. The box 23 may be formed of ma terials that will not take an excessive hardness when the body 22 is heat treated or that may be annealed after the heat treatment of the body to have the desired capabilities and characteristics.

In assembling the point on the tooth base the unit or point comprising the body 22 and the box 23 is first slid over the wedge-shaped tooth part I3. When the point is being passed rearwardly or inwardly over the part I3 the tang 23 enters the opening I3. The cap or point is moved inwardly on the tooth part I3 until the lower surface of the body 22 evenly engages against the upper surface I6 of the part I3 and the upper surface of the bottom wall 29 evenly engages against the lower surface I'I of the part I3. This limits the inward movement of the point on the part I3. The point is then in a position to be secured to the part I3 of the tooth base IIJ. This is accomplished by distorting or indenting the side walls 28 of the malleable box portion B to have indented parts 34 which cooperate with the recesses I3. The indentations or indented parts 34 may be formed in any suitable manner, for example, they may be squeezed or hammered in. The Letters Patent referred to above disclose a tool having screws for cooperating with the side walls 28 of the box 23 to force the same inwardly and thus provide the indented parts 34. The inwardly bent parts or indented parts 34 are in the nature of projections on the inner sides of the box walls 28 that cooperate with the recesses IB to dependably secure the point to the tooth base III. The indented parts 34 are opposite one another in coincident relation with a transverse axis that is at right angles to the longitudinal axis of the tooth.

In the use or operation of the excavating tooth the forwardly projecting spike portion or .spike of the body 22 is adapted to effectively penetrate the earth. The body 22 projects downwardly and forwardly beyond the box 23 so that it may penetrate the earth without interference by the box. The forwardly projecting spike portion of the body 22 also protects the box 23 against wear and injury. The body 22 overlies and directly bears on the upper surface I3 of the part I3 to directly transmit the operating loads and stresses to the part i3 when downward loads are imposed on the tooth point. The tang 25 engaging in the opening I9 effectively resists forces on the body 22 that tend to lift or tip the body upwardly with respect to the tooth base part I3. The tang 23 engaging in the opening I9 also operates to prevent lateral shifting and rocking of the tooth point on the part I3. The box 23 engaging about the part I3 of course assists in preventing the body 22 from shifting laterally and from rocking and tipping upwardly with respect to the part I3.

The indented parts 3B cooperating with the recesses I3 dependably prevent detachment or disengagement of the point from the tooth base part I3. The portion A of the housing or box 23 being formed of a rigid distortion resisting material prevents distortion of the box that might otherwise tend to cause loosening of the indented parts 3ft in the recesses I3. The box portion A closely engages about the sides I and the lower surface I'I of the part I3 to hold or to assist in holding the tooth point against lateral shifting and upward shifting and tilting. The portion A effectively resists distortion when the tooth point is subjected to heavy forces and prevents distortion of the box 23 that might result in loosening of the tooth point on the part I3. The improved housing or box 23 embodied in the tooth point of the present invention includes the strong rigid portion A that dependably prevents working and shifting of the point on the tooth oase part I3 and includes the malleable portion B that facilitates the rapid easy attachment of the tooth point to the tooth by providing it with the indented parts 33.

The improved tooth point of the present invention is such that it may be readily detached from the tooth for replacement or repair. When it is desired to remove the tooth point from the tooth base IS the point is forced outwardly or forwardly so that the indented parts 34 are bent or forced outwardly from the recesses IB. This may be accomplished in any convenient or desired manner. In the Letters Patent referred to above we have disclosed a wedge embodying wedge parts adapted to be forced between the opposing corners or surfaces 2i and il to force the point outwardly on the tooth base part I3. This outward forcing of the tooth point is accompanied by outward bending of the indented parts 3d resulting from engagement of the parte with the inclined walls of the recesses I3. Thus when the tooth point is driven from the base part I3 the side walls 23 of the malleable box portion B are straightened out.

Having described only a typical preferred form and application of our invention, we do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to ourselves any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claim.

Having described our invention, we claim:

A point adapted to be applied to the forward part of a tooth base, the sides of said part having recesses, the point including a hard wear-resisting metal body adapted to overlie the forward part of the base, to bear on its upper surface and project forward from said part, and a metal box secured to the body, arranged beneath the latter and forming therewith a structure adapted to embrace said part of the base, the box comprising separately formed forward and rear portions, the forward portion being adapted to snugly embrace a material part of the forward portion of said forward part and formed of a substantially unyielding metal to prevent distortion of the box and Working of the point on the tooth base, the rear portion being formed of malleable metal and adapted to be distorted to have indented parts engage in the recesses of the base to secure the point to the latter, and a connection integrally joining said front and rear portions of the box.

CHESTER C. HOSMER. ERNIE L. LAUNDER. 

